飞机大修精益管理实施方案

本文借鉴同行维修业的管理方法并结合南航A320飞机主维修基地自身的特点,利用精益生产管理的先进理念,创建了一套精益拉动式的生产管理体系.实践证明该管理体系适合企业自身特点,飞机大修工作的质量、周期、成本和生产效率等得到明显改善.     

飞行器再入时GNC系统一体化仿真研究

首先建立了飞行器再入时制导、导航和姿控ＧＮＣ系统一体的六自由度数学仿真模型。然后对如何消除控制系统和运动方程的交连影响和导航误差给落点精度带来的影响进行了分析和讨论同时还研究了六自由度弹道计算对导引和制导规律的影响，最后对飞行器再入时如针制导，导航和姿控系统组合在一起进行六自由度数学仿真进行了分析和研究，并讨论了一体化仿真可怕一些问题。     

回转体倾斜入水空泡试验及六自由度数值计算研究

为研究回转体倾斜入水空泡及参数变化,基于低速入水试验装置和CFD软件对该问题进行了试验和数值仿真研究。通过试验对回转体倾斜入水的空泡演变进行研究,得到了不同时刻空泡形态图。数值计算选用基于N-S方程的雷诺平均(RANS)方法和基于k-ω的SST二方程湍流模型,建立了六自由度数值仿真方法。结果表明:数值计算得到的空泡形态与试验结果一致性较好,依次经历了撞击水面、空泡形成、颈缩、空泡断裂、空泡闭合、表面紊乱和空泡溃灭的过程。进一步分析发现速度、加速度和压力均在入水瞬间和空泡断裂时刻发生波动;偏转角度在回转体尾部刺穿空泡后增幅明显;随着入水角度增加,入水瞬间速度衰减加快、压力峰值增加,峰值出现越早,空泡闭合越难。     

六自由度飞行实时仿真和功率谱法比较

大气紊流是飞机巡航状态中影响飞机运动的主要大气扰动现象,以奖状飞机和波音747为例,研究飞机受大气紊流影响所产生的飞行姿态变化。使用了两种方法进行飞行仿真,一种是基于六自由度飞行力学方程的实时仿真法,另一种是基于线性化小扰动方程组的响应频谱法。通过与试飞数据进行比较,分析两种方法的优缺点。研究表明,六自由度飞行实时仿真可以更好地模拟大型飞机大气扰动下的飞行状态,较准确地表征各项参数变化特性。     

Effects of swirler position on flame response and combustion instabilities

This study is concerned with the experimental and theoretical investigation of the combustion instabilities in a premixed swirl combustor. It is focused on the effects of the swirl mixing distance on the intrinsic thermoacoustic mode. The swirler as an origin of the swirling flow is also the source of the flow disturbance, which has effects on the flame response. The location of the swirler is varied in the experiment to study the effect on combustion instabilities and flame transfer functions. ...     

An FV-EE model to predict lean blowout limits for gas turbine combustors with different structures and sprays

The occurrence of Lean Blowout(LBO) is a disadvantage that endangers a stable operation of gas turbines. A determination of LBO limits is essential in the design of gas turbine combustors. A semiempirical model is one of the most widely used methods to predict LBO limits.Among the existing semiempirical models for predicting LBO limits, Lefebvre’s LBO model and the Flame Volume(FV) model are particularly suitable for gas turbine combustors. On the basis of Lefebvre’s and FV models, the concept o...     

Experimental investigation of a gliding discharge plasma jet igniter

Relight of jet engines at high altitude is difficult due to the relatively low pressure and temperature of inlet air. The penetration of initial flame kernel affects the ignition probability in the turbine engine combustor greatly. In order to achieve successful ignition at high altitude, a deeper penetration of initial flame kernel should be generated. In this study, a Gliding Arc Plasma Jet Igniter(GAPJI) is designed to induce initial flame kernel with deeper penetration to achieve successful ...